Journal article
The spectral energy distribution of powerful starburst galaxies - I. Modelling the radio continuum
TJ Galvin, N Seymour, J Marvil, MD Filipović, NFH Tothill, RM McDermid, N Hurley-Walker, PJ Hancock, JR Callingham, RH Cook, RP Norris, ME Bell, KS Dwarakanath, B For, BM Gaensler, L Hindson, M Johnston-Hollitt, AD Kapińska, E Lenc, B McKinley Show all
Monthly Notices of the Royal Astronomical Society | OXFORD UNIV PRESS | Published : 2018
Abstract
We have acquired radio-continuum data between 70MHz and 48 GHz for a sample of 19 southern starburst galaxies at moderate redshifts (0.067 < z < 0.227) with the aim of separating synchrotron and free-free emission components. Using a Bayesian framework, we find the radio continuum is rarely characterized well by a single power law, instead often exhibiting lowfrequency turnovers below 500 MHz, steepening at mid to high frequencies, and a flattening at high frequencies where free-free emission begins to dominate over the synchrotron emission. These higher order curvature components may be attributed to free-free absorption across multiple regions of star formation with varying optical depths...
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Awarded by National Aeronautics and Space Administration
Funding Acknowledgements
The authors would like to thank the anonymous referee whose comments and suggestions improved the presentation of this manuscript. The ATCA is part of the Australia Telescope National Facility, which is funded by the Commonwealth of Australia for operation as a National Facility managed by CSIRO. This paper includes archived data obtained through the Australia Telescope Online Archive (http://atoa.atnf.csiro.au). This scientific work makes use of the Murchison Radio-astronomy Observatory, operated by CSIRO. We acknowledge the Wajarri Yamatji people as the traditional owners of the Observatory site. Support for the operation of the MWA is provided by the Australian Government (NCRIS), under a contract to Curtin University administered by Astronomy Australia Limited. We acknowledge the Pawsey Supercomputing Centre, which is supported by the Western Australian and Australian Governments. RMcD is a recipient of an ARC Future Fellowship. Parts of this research were conducted by the Australian Research Council Centre of Excellence for All-Sky Astrophysics (CAASTRO), through project number CE110001020. This research has made use of the NASA/IPAC Extragalactic Database (NED), which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration.